6W7S

Ketoreductase from module 1 of the 6-deoxyerythronolide B synthase (KR1) in complex with antibody fragment (Fab) 2G10

6W7S の概要

• エントリーDOI: 10.2210/pdb6w7s/pdb
• 分子名称: EryAI, 2G10 (Fab heavy chain), 2G10 (Fab light chain), ... (6 entities in total)
• 機能のキーワード: ketoreductase, antibody fragment, oxidoreductase-immune system complex, oxidoreductase/immune system
• 由来する生物種: Saccharopolyspora erythraea; 詳細
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 103532.37

構造登録者

Cogan, D.P.,Mathews, I.I.,Khosla, C. (登録日: 2020-03-19, 公開日: 2020-09-09, 最終更新日: 2024-10-16)

主引用文献

Cogan, D.P.,Li, X.,Sevillano, N.,Mathews, I.I.,Matsui, T.,Craik, C.S.,Khosla, C.
Antibody Probes of Module 1 of the 6-Deoxyerythronolide B Synthase Reveal an Extended Conformation During Ketoreduction.
J.Am.Chem.Soc., 142:14933-14939, 2020

PubMed Abstract: The 6-deoxyerythronolide B synthase (DEBS) is a prototypical assembly line polyketide synthase (PKS) that synthesizes the macrocyclic core of the antibiotic erythromycin. Each of its six multidomain modules presumably sample distinct conformations, as biosynthetic intermediates tethered to their acyl carrier proteins interact with multiple active sites during the courses of their catalytic cycles. The spatiotemporal details underlying these protein dynamics remain elusive. Here, we investigate one aspect of this conformational flexibility using two domain-specific monoclonal antibody fragments (Fs) isolated from a very large naïve human antibody library. Both Fs, designated 1D10 and 2G10, were bound specifically and with high affinity to the ketoreductase domain of DEBS module 1 (KR1). Comparative kinetic analysis of stand-alone KR1 as well as a truncated bimodular derivative of DEBS revealed that 1D10 inhibited KR1 activity whereas 2G10 did not. Co-crystal structures of each KR1-F complex provided a mechanistic rationale for this difference. A hybrid PKS module harboring KR1 was engineered, whose individual catalytic domains have been crystallographically characterized at high resolution. Size exclusion chromatography coupled to small-angle X-ray scattering (SEC-SAXS) of this hybrid module bound to 1D10 provided further support for the catalytic relevance of the "extended" model of a PKS module. Our findings reinforce the power of monoclonal antibodies as tools to interrogate structure-function relationships of assembly line PKSs.

PubMed: 32786753
DOI: 10.1021/jacs.0c05133

実験手法

X-RAY DIFFRACTION (2.25 Å)